JPS5963213A - Air suspension device - Google Patents

Abstract

PURPOSE:To improve operating stability by so constituting that a right and a left air springs of an air suspension for a large vehicle using a pair of the right and left air springs are connected independently with an air tank through leveling valves which are opened and closed by links provided at regular intervals. CONSTITUTION:When a heavy load is applied to a vehicle body, for example, a pair of air springs 13 and 14 in a front side is bent, valves 15 and 16 are opened by moving operating levers 18 and 19 of the levelling valves 15 and 16 upward by links 20 and 21, air in a tank 17 is fed to the air springs 13 and 14, spring constants are improved, rolling rigidity is given and the vehicle body is prevented from sinking. In this instance, a state in a three-point support can be secured practically by making a distance l between the front links 20 and 21 less than 200mm. and a distance L between rear links 30 and 31 about 800mm.. The three-point support is maintained and operating stability can be improved in this manner.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air suspension system for a vehicle, and more particularly to an air suspension system in which an axle is suspended from a vehicle body via a pair of left and right air springs.

In large vehicles such as trucks and buses, leaf springs are used as chassis springs because they need to support a large vehicle weight, and they are hard and have a high spring constant. However, such chassis springs cannot completely isolate vibrations from the road surface, and for this reason, air suspension systems consisting of air springs are used in large vehicles where riding comfort is particularly important, such as buses. is now used.

The air suspension device is configured to suspend front and rear axles on a vehicle body via a pair of left and right air springs.

These air springs are each connected to an air tank via a leveling valve. The leveling valve supplies air from the air tank to the air springs or exhausts the air in the air springs to prevent changes in vehicle height due to loads applied to the vehicle body. In such an air suspension system, if the height of the air springs, which are provided in pairs at the front and rear, is adjusted independently via leveling valves, the height of the vehicle can be adjusted at four points. , the possibility of one wheel lifting occurs. Conventionally, the pair of air springs on the rear side were each provided with an independent leveling valve, which allowed the height to be adjusted independently.

On the other hand, the front axle 2, to which the front wheels 1 are attached at both ends, is suspended from the vehicle body via a pair of left and right air springs 3.4, as shown in FIG. At the same time, these air springs 3.4 are communicated with each other via a communication pipe 5, and this communication pipe 5
It was designed to be connected to an air tank 7 via a leveling valve 6. And the leveling valve 6 is
Its opening and closing was controlled by an operating lever 8 and a link 9. In other words, in the conventional air suspension system, the height of the front side of the system is adjusted using a common leveling valve 6 and a link 9, as shown in FIG. I was trying to establish that.

The disadvantage of such a conventional air suspension device is that the pair of air springs 3.4 on the front side are connected to each other by the communication pipe 5, so that the air springs 3.
．． 40 Roll rigidity was low, which caused the vehicle body to easily roll, impairing steering stability.

In other words, in the conventional air suspension device, by establishing three-point support for the vehicle body, the steering stability deteriorates.

The present invention has been made with the aim of overcoming such problems, and it does not impair the substantial three-point support of the vehicle, and also provides roll rigidity to the air spring to improve handling stability. It is an object of the present invention to provide an air suspension device as described above.

The present invention will be explained below with reference to an illustrated embodiment.

FIGS. 2 and 3 show the air suspension device according to this embodiment, and the front axle 12 on which the front wheels 11 are attached on both sides, especially as shown in FIG.
It is suspended from the vehicle body via a pair of left and right air springs 13 and 14. The air springs 13, 14 are each connected to the air tank 17 via a leveling valve 15, 16. The pair of leveling valves 15 and 16 are each provided with operating levers 18 and 19 to control opening and closing of these valves, and these operating levers 1
The tip of 8.19 is connected to link 20.21 via an elongated hole.

These links 20 , 21 extend parallel to each other and downward and are connected at their lower ends to the axle 12 . Furthermore, the distance B between these pair of links 20°21 is 2
The value is set to 00 mm or less, for example, 100 mn+.

Next, the rear axle 23, to which the rear wheels 22 are attached at both ends, is connected to a pair of air springs 24, 25, as shown in FIG.
It is suspended to the vehicle body via.

These air springs 24, 25 are also connected to the air tank 17 via leveling valves 26, 27, respectively. and leveling valve 26.
27 are each provided with operating levers 28, 29, and the tips of these operating levers 28, 29 are connected to the axle 23 via links 30, 31.

As described above, in the vehicle of this embodiment, the vehicle body has air springs 13, 14 and 24 at the front and rear parts.
．． 25, and these air springs prevent the vehicle body from receiving vibrations from the road surface.
Good riding comfort can be achieved. And depending on the load applied to the car body, these air springs 13.1
4 and 24.25 are supplied with air from an air tank 17, or these air springs 13.1
4 or 24.25 air is exhausted. That is, when a large load is applied to the vehicle body, for example, the pair of front air springs 13, 14 will deflect. Then the bottom end is axle 12
The links 20.21 connected to the levers 18.19 of the leveling valves 15.16 pivot upwardly, as shown in FIG. 2 by solid lines in each case. This allows the leveling valve 1 to be removed from the air tank 17.
Compressed air is supplied to the air springs 13 and 14 through 5.16, and the vehicle body is lifted to keep the height of the vehicle body approximately constant with respect to the road surface. Also, when the load on the vehicle body becomes lighter, the air springs 13, 14 expand upward, so that the links 20, 21, whose lower ends are connected to the axle 12, move the operating levers 18, 19, respectively, as indicated by chain lines in FIG. As a result, the exhaust port of the leveling valve 15.16 is closed, and the air inside the air spring 13.14 is exhausted to the outside through the leveling valve 15.16. In this way, the height of the vehicle body is lowered to a predetermined value. In addition, the air spring 24 on the rear side
．． 25 as well, since the leveling valves 26 and 27 work in the same way, the height of the vehicle can also be adjusted on the rear side.

Further, in the vehicle of this embodiment, the vehicle has substantially three
It is designed to be supported at a point. That is, as shown in FIGS. 2 and 3, a link 2 for controlling the opening and closing of the pair of leveling valves 15 and 16 on the front side.
0.21 means that the width direction of those vehicles is 200m.
The value is set to m or less. On the other hand, the distance between the links 30 and 31 that respectively control the opening and closing of the pair of leveling valves 26 and 27 on the rear side is set to a relatively large value, for example, about 8001 mm. Therefore, with such a configuration, the vehicle body is supported at substantially two points on the rear axle 23 on the rear side, and supported at substantially one point on the front side. That is, as shown in FIG. 4, a pair of leveling valves 15.1 on the front side
The distance between the pair of links 20 and 21 that open and close 6 is 200 m.
If the distance exceeds m, the difference in load applied to the left and right air springs 13, 14 becomes extremely large, and as a result, three-point support is effectively lost. For this, 200Il
If the distance between the links 20 and 21 is set to 1 m or less, the difference in load applied to the left and right air springs 13, 14 will be almost zero, thereby achieving substantial three-point support. Furthermore, as shown in FIG. 5, as the distance between the left and right links 20, 21 becomes wider, the effort required to adjust the vehicle's attitude becomes extremely large. This means that the spacing between links 20 and 21 is 20
This is because if it exceeds 0 mm or more, substantial three-point support cannot be achieved. As described above, in this vehicle, the links 20 and 21 are spaced apart from each other by 200 mm or less, so that the vehicle body can be substantially supported at three points.

Furthermore, in the vehicle of this embodiment, 4
Two air springs 13.14 and 24.25 independently control the leveling valves 15.16 and 26.2, respectively.
7 to the air tank 17, and these air springs 13, 14, 24, 25 are not connected to each other by a communicating tube that allows free air flow. Therefore four air springs 13, 14 and 24.
25 each have high roll rigidity, which prevents the vehicle body from wobbling. That is, even when the vehicle body turns, these air springs 13.
14.24.25 Roll stiffness 8- prevents rolling of the vehicle body, which improves handling stability.

As described above, according to the present invention, the pair of left and right air springs are connected to the air tank via the leveling valves, and the distance between the pair of links for opening and closing these leveling valves in the width direction of the vehicle is adjusted. 20
0 mm or less, by installing such an air suspension device at either the front or rear of the vehicle, it is possible to achieve substantial three-point support for the vehicle body, as well as to Roll stiffness can be imparted to each spring, thereby making it possible to improve the steering stability of the vehicle.

[Brief explanation of the drawing]

FIG. 1 is a front view of main parts showing a conventional air suspension device, FIG. 2 is a front view of main parts of an air suspension device according to an embodiment of the present invention, FIG. 3 is a plan view of the main parts, and FIG. The figure is a graph showing the difference in the load applied to the left and right air springs with respect to the distance between the pair of links for opening and closing the leveling valves provided in each pair of air springs. Figure 5 is the attitude of the vehicle with respect to the distance between the left and right links. 3 is a graph showing the man-hours for adjustment. In addition, in the symbols used in the drawings, 12...Axle 13.14...Air spring 15.16...Leveling valve 17...Air tank 20.21...Link. Applicant Hino Motors Co., Ltd. 11-41A4I? sgr-k) Koto 2 Rjw prayer to defeat the army-
6 tricks, 4 kisses, 94 items

Claims (1)

[Claims] In a device in which an axle is suspended from a vehicle body via a pair of left and right air springs, each of the pair of air springs is independently connected to an air tank via a leveling valve, and a device for opening and closing the pair of leveling valves is provided. The distance between a pair of links in the width direction of the vehicle is 2
An air suspension device characterized in that the distance is within 0.0111 m.